This invention relates to a control apparatus for a variable valve actuating mechanism or a variable valve control apparatus which is configured to improve the fuel consumption and the combustion by retarding a closing timing of an intake valve when the engine shifts to a low and middle load region.
A conventional internal combustion engine needs uniformity or evenness of air-fuel mixture which affects fuel consumption and exhaust emission performance in a partial load (low and middle load) region.
Specifically, in an in-cylinder direct fuel-injection engine, the fuel is directly injected into the cylinder. The air-fuel mixture does not generate in advance in an intake pipe. Accordingly, it is difficult to generate the uniform or even air-fuel mixture. Moreover, the gas flow speed of the flesh air decreases in the low speed. This is disadvantageous to uniformize the air-fuel mixture. Moreover, the fuel injection quantity increases in a slightly high partial load region, and it is more difficult to uniform the air-fuel mixture.
Therefore, a patent document 1 (U.S. Pat. No. 6,065,444 (corresponding to Japanese Patent Application Publication No. 11-182329)) and a patent document 2 (Japanese Patent Application Publication No. 2003-106177) disclose flow regulating valves arranged to forcibly generate a swirl and a tumble in an intake port for producing the uniform air-fuel mixture within the combustion chamber in the partial load.